This application is based on Japanese Patent Application No. 2002-91316 filed on Mar. 28, 2002, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a seat air-conditioning unit for a vehicle, which supplies conditioned air to a seat of the vehicle.
2. Background of the Invention
In a seat air conditioning unit for a vehicle disclosed in JP-A-2000-152849 (U.S. Pat. No. 6,179,706), air is introduced into an air passage formed in a seat by a blower unit, and blown from a seat surface. The air passage includes a plurality of air distribution passages extending along the seat surface and an air introduction passage introducing the air from the blower unit into the air distribution passages.
The air distribution passages are diverged from a downstream end of the air introduction passage and linearly extended in a front and rear direction or a top and bottom direction of the seat. Downstream ends of some air distribution passages are open at the sides of the seat. Also, the downstream end of the air introduction passage is located at a portion which receives seating pressure by a user.
Therefore, the air is not directly blown off from the seat surface just above the downstream end of the air introduction passage, but can be diverged into the air distribution passages from the downstream end of the air introduction passage. Further, the air can smoothly flow in the distribution passages without causing heat loss, thereby improving air conditioning performance.
However, since the air is blown through the seat surface along the air distribution passages extending in the front and rear or the top and bottom direction of the seat. Therefore, it is difficult to blow the air widely in the right and left direction of the seat. To provide expansion of the air conditioning effect, it may be possible to increase the number of the air distribution passages or to widen the air distribution passages. However, it is likely to decrease seating comfort.
The present invention is made in view of the above disadvantage, and it is an object of the present invention to provide a seat air conditioning unit for a vehicle that provides air conditioning effect widely over a seat surface without decreasing seating comfort.
According a seat air conditioning unit for a vehicle of the present invention, a seat has a seat member forming an air passage through which air blown by a blower unit flows and an air permeable seat surface member disposed on the surface of the seat member. The seat member includes a main pad and an air permeable sub pad. The sub pad is provided between the main pad and the seat surface member. The air passage includes an air introduction passage, a plurality of air distribution passages formed on a surface of the main pad adjacent to the sub pad and through holes formed in the sub pad at portions corresponding to the air distribution passages. The air introduction passage introduces air from the blower unit into the air distribution passages. The air distribution passages diverged from the air introduction passages and extend toward an end of the seat member. The through holes have openings on a surface of the sub pad adjacent to the seat surface member. A dimension of each opening is greater than a dimension of the air distribution passage in a direction substantially perpendicular to a longitudinal direction of the air distribution passage.
Air introduced in the air distribution passages is blown toward a seat user through the sub pad and the seat surface member. Since the dimension of the opening is greater than the dimension of the air distribution passage in the direction substantially perpendicular to the longitudinal direction of the air distribution passage, the flow of the air can expand while passing through the through holes. Therefore, the air can be blown toward the seat user widely over the seat surface member without increasing in the number and the width of the air distribution passages. Accordingly, the seat air conditioning unit can provide an air conditioning effect widely over the seat surface, without decreasing seating comfort.